More money is being spent on running the Child Support Agency's enforcement unit than it recovers from fathers, it emerged today.

The agency, which recovers maintenance from absent parents for the upkeep of their children, retrieved £8 million last year, but cost £12 million to operate.

A spokeswoman for the Department for Work and Pensions, which is responsible for the CSA, said while the figures were accurate, they only accounted for money retrieved from the initial contact with the parent and did not take into account any future payments made by that person.

She said: "These figures are just the tip of the iceberg.

"They take into account just the initial payment that's made from the enforcement action. That is just an initial contact. It doesn't take into account how much will then by collected from that person in the future."

The CSA has recently come under fire after Tony Blair admitted it was "not properly suited" to its job.

During a question time exchange with Liberal Democrat leader Charles Kennedy, the Prime Minister said that the Government was "looking urgently" at solutions to its cash problems.

Mr Blair told MPs that the CSA was an investigating, adjudicating and enforcement agency all rolled into one and that made it "extremely difficult" for it to operate cost-effectively.

He was responding to claims by Mr Kennedy that the CSA had "an appalling track record" and that for every £1 it spent on bureaucratic costs, it only got £1.85 through to children.

The CSA has been plagued by systems problems, with the result that many lone parents have not received payments they were due, and hundreds of millions of pounds in non-collected maintenance has been written off.

But Downing Street has played down suggestions that it may be scrapped, with its functions split between different bodies.

The new figures emerged from a parliamentary question asked by Paul Goodman, the Conservative MP for Wycombe.

A review of the agency is being carried out by its chief executive, Stephen Geraghty, and is due to report at the end of this year or early in 2006.